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Application Of Biologically Activate Carbon For Treatment Of Sulfide-Laden Groundwater, Jessica Cormier Jan 2022

Application Of Biologically Activate Carbon For Treatment Of Sulfide-Laden Groundwater, Jessica Cormier

Electronic Theses and Dissertations, 2020-2023

Small-system water purveyors must overcome many challenges to provide an adequate and safe water supply to its consuming public. This dissertation reports on research related to the application of biologically activated carbon (BAC) media filters for the treatment of well water to remove disinfection by-product (DBP) precursor matter, measured as dissolved organic carbon (DOC), at two treatment plants serving a small community water system. Four research questions were investigated individually in discrete, yet interconnected studies at two water treatment facilities processing groundwater that contained hydrogen-sulfide (~1.2 mg/L) and dissolved organic carbon (~2.0 mg/L). The first study revealed that BAC filters …


Integrated Electro-Optic, Microwave, And Nonlinear Photonic Devices On Thin-Film Lithium Niobate, Milad Gholipour Vazimali Jan 2022

Integrated Electro-Optic, Microwave, And Nonlinear Photonic Devices On Thin-Film Lithium Niobate, Milad Gholipour Vazimali

Electronic Theses and Dissertations, 2020-2023

Lithium niobate has numerous extraordinary features that make it useful for a wide range of applications, particularly in optics. The material's strong electro-optic effect and second-order nonlinearities are two prime examples with applications in optical modulation and wavelength conversion, respectively. The thin-film lithium niobate platform has revitalized the conventional applications of lithium niobate during the last decade. The platform is now one of the most actively investigated subdisciplines in integrated photonics. The waveguides on this innovative platform are high index contrast, resulting in a size reduction of more than 20 times and a bending radius decrease of about two orders …


Cinematic Practices: An Evaluation Of Production Theories In Service Of Micro-Budget Feature Film-Making, Andrew Myerson Jan 2022

Cinematic Practices: An Evaluation Of Production Theories In Service Of Micro-Budget Feature Film-Making, Andrew Myerson

Electronic Theses and Dissertations, 2020-2023

Bottom of a Glass Blues and its accompanying dissertation, Cinematic Practices are the basis of research into production practices used by independent and micro-budget filmmakers in the Central Florida community. The research presented in this dissertation is used to satisfy the academic requirements for the University of Central Florida's Master of Fine Arts in Feature Film Production. Cinematic Practices evaluates production theories used in studio and independent film-making in the present day in addition to practices popularly embraced by local filmmakers in Central Florida. The research found that there is no shared knowledge on how to organize film crews for …


Biomimetic Design, Modeling, And Adaptive Control Of Robotic Gripper For Optimal Grasping, Mushtaq Al-Mohammed Jan 2022

Biomimetic Design, Modeling, And Adaptive Control Of Robotic Gripper For Optimal Grasping, Mushtaq Al-Mohammed

Electronic Theses and Dissertations, 2020-2023

Grasping is an essential skill for almost every assistive robot. Variations in shape and/or weight of different objects involved in Activities of Daily Living (ADL) lead to complications, especially, when the robot is trying to grip novel objects for which it has no prior information –too much force will deform or crush the object while too little force will lead to slipping and possibly dropped objects. Thus, successful grasping requires the gripper to immobilize an object with the minimal force. In Chapter 2, we present the design, analysis, and experimental implementation of an adaptive control to facilitate 1-click grasping of …


Automated Vehicle To Vehicle Conflict Analysis At Signalized Intersections By Camera And Lidar Sensor Fusion, Alabi Mehzabin Anisha Jan 2022

Automated Vehicle To Vehicle Conflict Analysis At Signalized Intersections By Camera And Lidar Sensor Fusion, Alabi Mehzabin Anisha

Electronic Theses and Dissertations, 2020-2023

This research presents an approach for safety diagnosis using sensor fusion techniques. This work fuses the outputs of a roadside low-resolution camera and a solid-state LiDAR. For vehicle classification and detection in videos, the YOLO v5 object detection model was utilized. The raw 3D point clouds generated by the LiDAR are processed by two manual steps - ground plane transformation and background segmentation, and two real-time steps - foreground clustering, and bounding box fitting. Taking the generated 2D bounding boxes of both camera and LiDAR, we associate the common bounding box pairs by thresholding on the Euclidean distance threshold of …


Development Of A Multivariate Poisson Hidden Markov Model For Application In Educational Data Mining, Shahab Boumi Jan 2022

Development Of A Multivariate Poisson Hidden Markov Model For Application In Educational Data Mining, Shahab Boumi

Electronic Theses and Dissertations, 2020-2023

Managers and policymakers in higher education institutions try to improve graduation rates and decrease halt rates. To achieve this goal, it is important to understand academic and demographic factors that correlate with academic performance. Many studies in the field of education analytics have identified student grade point averages (GPA) as an important indicator and predictor of final academic outcomes (graduating or halting their studies). While semester-to-semester fluctuations in GPA are considered normal, significant changes in academic performance may warrant more thorough investigation and consideration, particularly with regard to final academic outcomes. However, it is challenging to represent complex academic trajectories …


Designing Physical And Chemical Confinement In Lithium Sulfur Battery Cathode For Suppression Of Shuttle Effect, Saisaban Fahad Jan 2022

Designing Physical And Chemical Confinement In Lithium Sulfur Battery Cathode For Suppression Of Shuttle Effect, Saisaban Fahad

Electronic Theses and Dissertations, 2020-2023

Lithium sulfur batteries (LSBs) are attracting attention as a next generation energy storage device because of their high energy density (2670WhKg-1), high specific capacity (1675 mAhg-1), low cost and environmental friendliness. However, there are several challenges that need to be overcome before LSBs can be implemented in general applications. This is due to the low electric conductivities of sulfur and lithium sulfide and large volume changes during charge/discharge cycling. Also, most importantly, the dissolution of lithium polysulfides into the electrolyte during cycling leads to capacity decay and low coulombic efficiency. Additionally, these lithium polysulfides can diffuse to the lithium anode …


Humans In Algorithms, Algorithms In Humans: Understanding Cooperation And Creating Social Ai With Causal Generative Models, Lux Miranda Jan 2022

Humans In Algorithms, Algorithms In Humans: Understanding Cooperation And Creating Social Ai With Causal Generative Models, Lux Miranda

Electronic Theses and Dissertations, 2020-2023

Cooperation is the hallmark human trait which has allowed us to congregate into the vast, continent-sprawling societies we live in today. Yet, the precise social, environmental, and cognitive mechanisms which enable this cooperation are not fully understood. Toward this, lucrative insights have been borne through the use of formal computational models of socio-cognitive phenomena: In simulating our own cooperative behavior, we can better deduce the exact factors which cause it. The combined knowledge of these factors and ability to computationally simulate them allows us to further two goals: First, it empowers us with the knowledge of how to modify our …


Multi-Element Mobile Optical Wireless Communication Networks, Pooya Nabavi Jan 2022

Multi-Element Mobile Optical Wireless Communication Networks, Pooya Nabavi

Electronic Theses and Dissertations, 2020-2023

The capacity of traditional wireless radio-frequency (RF) networks such as wireless fidelity (Wi-Fi) is insufficient to meet ever-increasing demand for bandwidth stemming from growth in smart, connected devices. The omni-directional nature of RF signals does not allow easy solutions that involve adding more access points to support more devices and capacity because they start to interfere with each other. Optical wireless communications (OWC) have already extended the superb bandwidth capacity of wired optical datalinks to sites that cannot be connected by traditional optical fibers, such as satellites and disaster recovery areas. Development of OWC technologies for dense, multi-user environments promises …


Energy And Area Efficient Machine Learning Architectures Using Spin-Based Neurons, Hossein Pourmeidani Jan 2022

Energy And Area Efficient Machine Learning Architectures Using Spin-Based Neurons, Hossein Pourmeidani

Electronic Theses and Dissertations, 2020-2023

Recently, spintronic devices with low energy barrier nanomagnets such as spin orbit torque-Magnetic Tunnel Junctions (SOT-MTJs) and embedded magnetoresistive random access memory (MRAM) devices are being leveraged as a natural building block to provide probabilistic sigmoidal activation functions for RBMs. In this dissertation research, we use the Probabilistic Inference Network Simulator (PIN-Sim) to realize a circuit-level implementation of deep belief networks (DBNs) using memristive crossbars as weighted connections and embedded MRAM-based neurons as activation functions. Herein, a probabilistic interpolation recoder (PIR) circuit is developed for DBNs with probabilistic spin logic (p-bit)-based neurons to interpolate the probabilistic output of the neurons …


Synthesis And Characterization Of P-Type Transparent Conducting Copper Gallium Oxide Thin Films, Ashwin Kumar Saikumar Jan 2022

Synthesis And Characterization Of P-Type Transparent Conducting Copper Gallium Oxide Thin Films, Ashwin Kumar Saikumar

Electronic Theses and Dissertations, 2020-2023

Transparent conducting oxides (TCO) are a special class of materials that possess both the properties of optical transparency and electrical conductivity. They find use in various applications such as flat panel displays, light-emitting diodes, solar cells, touch screens, smart windows, etc. Some of the most well-known and widely used TCOs are ZnO doped with Al, In2O3 doped with Sn, and SnO2 doped with F. All these TCOs are n-type in nature and show n-type conductivity. On the contrary, p-type TCOs are not very common, and due to their inherent low mobility, it is very challenging to synthesize highly conductive p-type …


Exploring The Predictors Of And The Relationship Between Evidence Cultures And Flood Risk Management Performance, Jenna Tyler Jan 2022

Exploring The Predictors Of And The Relationship Between Evidence Cultures And Flood Risk Management Performance, Jenna Tyler

Electronic Theses and Dissertations, 2020-2023

Over the past two decades, public organizations have been encouraged and, at times, required to incorporate evidence in their decision-making processes. Evidence broadly refers to data and or knowledge that is gathered, analyzed, and used to generate a conclusion. Despite arguments and the intrinsic assumption that using evidence to inform decisions will improve organizational performance, there is limited empirical research to support this assertion. The proposed study addresses this gap in research and others in the context of local flood risk management. Specifically, using primary data gathered from local floodplain managers and secondary data from the US Census and the …


Generative Adversarial Networks For Extrapolation Of Corrosion In Automobile Images, Andre Von Zuben Jan 2022

Generative Adversarial Networks For Extrapolation Of Corrosion In Automobile Images, Andre Von Zuben

Electronic Theses and Dissertations, 2020-2023

Deep learning has shown success in several applications involving pattern recognition, expert systems, and scientific discovery. However, existing methods struggle with industrial applications, which are often challenged by non-ideal datasets. In many cases, the datasets are small, poorly labeled, noisy, or have unbalanced class distribution or any combination of such problems. In this Master's research, we propose a generative adversarial network (GAN) strategy that is able to circumvent limitations imposed by tiny datasets. As a case study, we use the extrapolation of corrosion in automobiles and feed our deep learning framework with only a few dozen images instead of the …


Supporting Secondary Teachers' Proof And Justification Of Calculus Concepts Through The Intentional Use Of Dynamic Technology, Shahabeddin Abbaspour Tazehkand Jan 2022

Supporting Secondary Teachers' Proof And Justification Of Calculus Concepts Through The Intentional Use Of Dynamic Technology, Shahabeddin Abbaspour Tazehkand

Electronic Theses and Dissertations, 2020-2023

Learning calculus concepts plays a huge role in understanding phenomena in STEM-related disciplines. Those concepts tend to be dynamic in nature, and the visual exploration and representation of calculus concepts using paper and pencil is limited compared to pedagogically and intentionally using dynamic geometry software. As such, a primary component of this dissertation study involves the integration of dynamic technology. Additionally, previous studies have shown that students have difficulties constructing proofs related to calculus concepts. Despite the existing body of research on students' comprehension of proof and justification, there has not been much focus on teachers' knowledge and perception of …


Simulation Of A Comprehensive Heat Recovery Steam Generator, Jose Chalarca Castro Jan 2022

Simulation Of A Comprehensive Heat Recovery Steam Generator, Jose Chalarca Castro

Electronic Theses and Dissertations, 2020-2023

With the increasing prevalence of renewables, it is important to optimize combined cycle power plants during transient conditions to better compliment the variable generation of renewable energy generators. There is a demand for dynamic heat recovery steam generators (HRSG) models that may enable improved control designs. Sufficiently accurate real-time simulations of HRSGs may serve as soft sensors and state estimators during transient conditions. Furthermore, real-time simulations of HRSGs can be used for operator training which does not incur the inherit risk of using plant hardware. The focus of this research is on the development towards an integrated dynamic closed loop …


Impact Of Ethnomodeling Explorations On Secondary Mathematics Pre-Service Teachers' Perceptions Of Teaching And Learning Geometry: A Multi-Case Study, Siddhi Desai Jan 2022

Impact Of Ethnomodeling Explorations On Secondary Mathematics Pre-Service Teachers' Perceptions Of Teaching And Learning Geometry: A Multi-Case Study, Siddhi Desai

Electronic Theses and Dissertations, 2020-2023

Through a focus on the intersection of mathematical modeling, ethnomathematics, and cultural and historical practices, this ethnomodeling research study intentionally connected efforts to engage and value each and every student's culture and identity while emphasizing essential geometry content. The data collection took place at a large Hispanic-serving public metropolitan research university in an undergraduate secondary mathematics education methods course intended for pre-service teachers (PSTs). Over the course of eight weeks PSTs completed a questionnaire and pre-/post-surveys, two individual assignments, three small-group tasks, three task reflections, and a group reflection which were then analyzed using quantitative and qualitative methods. In addition …


An Investigation Of The Excess Credit Hour Surcharge Policy And Its Impact On First-Time-In-College Students At A Large Metropolitan University In The State Of Florida, Lynn Grabenhorst Jan 2022

An Investigation Of The Excess Credit Hour Surcharge Policy And Its Impact On First-Time-In-College Students At A Large Metropolitan University In The State Of Florida, Lynn Grabenhorst

Electronic Theses and Dissertations, 2020-2023

An Excess Credit Hour policy "assesses a tuition surcharge for any credits taken beyond a predetermined threshold" (Smith, 2017, para. 1). In 2009, the State of Florida implemented legislation on excess credit hours at four-year public institutions, Fla. Stat. § 1009.286 (State of Florida, 2012). Legislation found under title forty-eight (XLVIII) of the K-20 Education Code, Fla. Stat. § 1009.286, relating to "Educational Scholarships, Fees, and Financial Assistance," discussed the "intent of the Legislature to encourage each undergraduate student who enrolls in a state university to complete the student's respective baccalaureate degree program in the most efficient way possible…" (State …


The Lived Experiences Of Faculty In The Covid-19 Pandemic Shift In Instruction, Alison Hammack Jan 2022

The Lived Experiences Of Faculty In The Covid-19 Pandemic Shift In Instruction, Alison Hammack

Electronic Theses and Dissertations, 2020-2023

This study sought to understand the lived experiences of mathematics faculty teaching during the COVID-19 pandemic's rapid shift from on-campus instruction to online education. Faculty are the primary influencers at a college. Their perspectives on the challenges and changes to teaching practices may determine a college's response to improving teaching and learning during a crisis. At the time of the COVID-19 transition, many faculty had no experience creating and teaching an online course, and some had previously been resistant to teaching online. Using a phenomenological approach, nine participants at a large state college were interviewed using the Teacher-Centered Systemic Reform …


Assessing Public Perception And Proposing An Organized Questionnaire For The Deployment And Adoption Of Autonomous Vehicles, Md Rakibul Islam Jan 2022

Assessing Public Perception And Proposing An Organized Questionnaire For The Deployment And Adoption Of Autonomous Vehicles, Md Rakibul Islam

Electronic Theses and Dissertations, 2020-2023

Since the general public will play a central role in the evolution of AVs, research has been performed to assess their perception and acceptance of AVs. Nevertheless, the most potential users of AVs, i.e., young, students, and more educated people, have not received any particular focus in those studies. This research gap has motivated us to assess their perceptions. Extensive data analyses of the survey at the University of Central Florida with a sample of 315 reveal that on average 57% of the respondents were familiar with AVs, and about 44% of the respondents felt positive perceptions toward AVs. Around …


The Fluid Dynamics Of A Spanwise-Morphing Wing: An Experimental And Analytical Study, Kamlesh Joshi Jan 2022

The Fluid Dynamics Of A Spanwise-Morphing Wing: An Experimental And Analytical Study, Kamlesh Joshi

Electronic Theses and Dissertations, 2020-2023

The unsteady forces and fluid flow structure of a morphing wing are investigated for low Reynolds number (Re) flows, i.e., Re < 20,000. The morphing wing is designed to change shape in the spanwise direction in a controlled manner using internal actuation. The two types of wing morphing are studied in this work, i.e., spanwise bending and spanwise twisting. The wing morphing is named based on the overall shape of the wing after it is dynamically morphed.


Translations To Support Loop Invariant Generation In Jml, Kohei Koja Jan 2022

Translations To Support Loop Invariant Generation In Jml, Kohei Koja

Electronic Theses and Dissertations, 2020-2023

Software is used in many critical systems in the real world such as autonomous cars and medical devices. Such software must be reliable to protect the general public. One standard way to make reliable software is to use Hoare-style verification techniques. However, for Hoare-style verification of loop correctness, loop invariants are necessary but are difficult for people to write themselves. Since Java is one of the most popular programming languages in the world, it is useful to have a tool to generate loop invariants for Java programs. OpenJML is a widely used program verification tool for Java. However, it does …


Investigating Covariate Selection Criteria: To Draw Causal Inferences From Observational Data In The Presence Of Unmeasured Covariates Using Regression And Propensity Score Methods, Uday Nair Jan 2022

Investigating Covariate Selection Criteria: To Draw Causal Inferences From Observational Data In The Presence Of Unmeasured Covariates Using Regression And Propensity Score Methods, Uday Nair

Electronic Theses and Dissertations, 2020-2023

The aim of causal effect estimation is to find the true impact of a treatment or exposure. Observational data is employed in social sciences to estimate causal effect but is susceptible to self-selection and unobserved confounding biases. Covariates included in analysis should strive to address these biases. This research focuses on investigating covariate selection approaches––common cause criterion (CC), Disjunctive Cause Criterion (DCC), Modified Disjunctive Cause Criterion (MDCC), and modified cause criterion (MCC)––in linear regression (LR) and propensity score methods (PSM) causal effect estimation in the presence of unmeasured confounding. Realistic social science scenarios such as––inclusion of proxy variables with varying …


Exploration Of Shock-Droplet Ignition And Combustion, John Patten Jan 2022

Exploration Of Shock-Droplet Ignition And Combustion, John Patten

Electronic Theses and Dissertations, 2020-2023

Liquid fuels are desirable in aerospace applications due to their higher energy density when compared to gaseous fuels. With the advent of detonation-based engines, it is necessary to characterize and analyze how liquid fuel interacts with detonation waves as well as shocks to ignite. While liquid fuel sprays have been proven to successfully aid and sustain detonations, the physical mechanism by which the individual liquid droplets accomplish this is yet to be understood. Such knowledge allows for more predictable detonation properties, which in turn can let detonation-based engines be sustained more easily. This research seeks to quantify and characterize interactions …


Effficient Graph-Based Computation And Analytics, Bingbing Rao Jan 2022

Effficient Graph-Based Computation And Analytics, Bingbing Rao

Electronic Theses and Dissertations, 2020-2023

With data explosion in many domains, such as social media, big code repository, Internet of Things (IoT), and inertial sensors, only 32% of data available to academic and industry is put to work, and the remaining 68% goes unleveraged. Moreover, people are facing an increasing number of obstacles concerning complex analytics on the sheer size of data, which include 1) how to perform dynamic graph analytics in a parallel and robust manner within a reasonable time? 2) How to conduct performance optimizations on a property graph representing and consisting of the semantics of code, data, and runtime systems for big …


Space-Time Photonics, Abbas Shiri Jan 2022

Space-Time Photonics, Abbas Shiri

Electronic Theses and Dissertations, 2020-2023

Many of the features of photonic devices, including some of the most ubiquitous components such as resonators and waveguides, are usually thought to be intrinsically dependent on their geometry and constitutive materials. As such, the behaviour of an optical field interacting with such devices is dictated by the boundary conditions imposed upon the field. For instance, the resonant wavelengths and linewidths of a planar cavity are expected to be set by the mirrors' reflectivity, cavity length, and refractive index. Henceforth, satisfying a longitudinal phase-matching condition allows for incident light to resonate with the cavity. As another example, consider the planar …


Towards Secure And Trustworthy Iot Systems, Lan Luo Jan 2022

Towards Secure And Trustworthy Iot Systems, Lan Luo

Electronic Theses and Dissertations, 2020-2023

The boom of the Internet of Things (IoT) brings great convenience to the society by connecting the physical world to the cyber world, but it also attracts mischievous hackers for benefits. Therefore, understanding potential attacks aiming at IoT systems and devising new protection mechanisms are of great significance to maintain the security and privacy of the IoT ecosystem. In this dissertation, we first demonstrate potential threats against IoT networks and their severe consequences via analyzing a real-world air quality monitoring system. By exploiting the discovered flaws, we can impersonate any victim sensor device and polluting its data with fabricated data. …


Quantification Of The Aerodynamic Drivers Of A Deployable Propeller, David Malyszek Jan 2022

Quantification Of The Aerodynamic Drivers Of A Deployable Propeller, David Malyszek

Electronic Theses and Dissertations, 2020-2023

With the use deployable drones becoming more common research into their improvement is necessary. Deployable drones that are launched from tubes have size limits on the diameter of the propeller during launch and storage. The purpose of this research is to develop deployable propeller blades for practical uses, such as tube launched propeller driven drones and easier to transport wind turbine blades. A deployable propeller will allow for the utilization of larger propellers when a large non-deployable blade isn't an option. Because deployable propellers need to fold, the deployable propeller blades were designed to be hollow and with a slit …


Hydrogen And Peer-To-Peer Energy Exchanges For Deep Decarbonization Of Power Systems, Hamed Haggi Jan 2022

Hydrogen And Peer-To-Peer Energy Exchanges For Deep Decarbonization Of Power Systems, Hamed Haggi

Electronic Theses and Dissertations, 2020-2023

Decreasing costs of renewable energy resources and net-zero emission energy production policy, set by U.S. government, are two preeminent factors that motivate power utilities to deploy more system- or consumer-centric distributed energy resources (DERs) to decarbonize electricity production. Since, deep energy decarbonization cannot be achieved without high penetration of renewable energy sources, utilities should develop and invest in new business models for power system operation and planning during the energy transition. Considering the pathways to deeply decarbonize power systems, first, this dissertation proposes a novel hierarchical peer-to-peer (P2P) energy market design in active distribution networks. The framework integrates the distributional …


Designing The Electrochemical Interface To Enable Lithium Metal Batteries, Supriya Koul Jan 2022

Designing The Electrochemical Interface To Enable Lithium Metal Batteries, Supriya Koul

Electronic Theses and Dissertations, 2020-2023

Although Li-ion battery is one of the most widely used energy storage devices, there have been extensive efforts to push its limit to meet the ever-increasing demands to improve its energy density for applications such as electric vehicles, portable electronics, and grid storages. Here, Li metal anode plays a key role in the next generation energy storage devices, ultimately enabling the anode-free configuration. However, there are major challenges that need to be overcome for a successful deployment of anode-free batteries. These include designing a competitive SEI, low Coulombic efficiency, and the formation of dendrites. To realize an effective anode-free configuration …


How Small Organic Osmolytes Modulate Actin Filament Assembly Kinetics And Mechanics, Pavlo Kravchuk Jan 2022

How Small Organic Osmolytes Modulate Actin Filament Assembly Kinetics And Mechanics, Pavlo Kravchuk

Electronic Theses and Dissertations, 2020-2023

Actin filament assembly and mechanics are crucial for muscle contraction, maintenance of cell structure, motility, and division. Actin filament assembly occurs in a crowded intracellular environment consisting of various types of molecules, including small organic molecules known as osmolytes. Ample evidence highlights the protective functions of osmolytes such as trimethylamine-N-oxide (TMAO), including their effects on protein stability and their ability to counteract cellular osmotic stress. Recently, TMAO has been shown to counteract the denaturing effects of urea on actin filament assembly based on bulk fluorescence assays. Yet, how TMAO affects individual actin filament assembly dynamics and mechanics is not well …